There is an extensive body of prior art that addresses solving the problem of how, with the aid of a liquid, to cool down a tool holder again that has been subjected to a heat application and then to effectively dry it.
Roughly summarized, three different cooling principles have been proposed up to this point. Namely air cooling, liquid cooling, and cooling through contact with a solid, i.e. by bringing the surface of the tool holder to be cooled into intimate contact with a very thermally conductive cooling element into which the heat flows.
The technologies that have been known up to this point and their disadvantages are described in detail in the older, but not published German patent application of the applicant, identified under the serial number DE 10 2009 034 730.
In order to solve the problems of the known prior art, in the above-mentioned older, but not published German patent application, the applicant proposes a device that makes use of a carrier gas flow guided in the circuit, into which a cooling liquid is misted in fine droplet form. It is thus possible to cool the work piece effectively and very uniformly, without excessively wetting it.
However, internal testing by the applicant has shown that even this device, which already works particularly well, can be further improved upon because this device may in fact be able to quite effectively dry the work pieces, which are in any case wetted only slightly, because the misting of the cooling liquid is stopped and the pure carrier gas flow, which is no longer charged with the cooling liquid droplets, continues to circulate turbulently around the work piece for a while longer, thus drying it.
When drying with the aid of the device known from these older applications, the main flow direction of the rapid, turbulent carrier gas flow is oriented essentially in the direction of the longitudinal axis of the work piece. This naturally results in the fact that in the region of recesses such as circumferential grooves or counterbores for set screws and the like, “lee zones”—figuratively speaking—form (in a quickly flowing body of water, they would be referred to as “dead water zones”) in which cooling liquid residues can collect beyond the end of the drying cycle, without being entrained with and removed by the carrier gas flow circulating turbulently around the work piece.
As internal testing has shown, this problem also could not be completely solved by turbulence-generating devices installed in the carrier gas flow just upstream of the region of the work piece to be dried, the task of which devices was to create even more intense turbulence in the carrier gas flow still flowing chiefly in the direction of the longitudinal axis of the work piece and/or to provide it with a swirling motion.
In view of this, the object of the present invention is to disclose a device for air-drying a work piece that has previously been subjected to a liquid application (washing and/or cooling), which is able to dry the work piece more quickly and reliably. This object should be attained primarily, but not exclusively, for work pieces that are essentially rotationally symmetrical around a longitudinal axis of the work piece and have a difficult-to-dry region that tapers toward one end. In a tool chuck for which this object should in particular be attained, this is the region that extends from the maximum diameter of the tool chuck to the sleeve part that holds the shaft of the tool.